It has been observed that the main cause of unborn baby fatalities in traffic accidents is death of the mother. While pregnant, most women either drive cars or are passengers in them. Thus, protecting mothers and reducing their risk of death in an accident indirectly implies protecting the unborn baby.
It is known that seatbelts are the most effective passive safety devices. Several studies have shown satisfactory results when using a three-point seatbelt, which once buckled is divided into two segments or belts: a shoulder strap that retains the upper body, and a lap belt that retains the hips.
These studies show that the lap belt must be as low as possible and close to the hips, never on the stomach or abdomen, while the shoulder belt must lie between the breasts, on the middle part of the sternum and on the centre of the collarbone, avoiding its position over a single breast, and pass around the abdomen and not above it. The height of the shoulder strap must be adjusted to keep it away from the neck but in contact with the shoulder, as well as close to the body, not loose.
However, the anatomical shape of pregnant women, particularly during late pregnancy, makes it difficult to position the seatbelt properly, implying a reduced efficacy of this device and a higher risk to the unborn baby.
Specifically, an incorrect position of the shoulder strap can cause lacerations to the neck. In addition, the lower part of the shoulder strap can slide above the midsection, potentially causing detachment of the placenta or crushing the unborn baby due to the mother's inertia during the impact.
In addition, the lap belt, even if it is initially positioned correctly under the abdomen, can easily move upward in case of strong braking or if the pregnant women moves, which can place the woman and unborn baby in a dangerous situation. In case of accident, if this belt is incorrectly positioned or is not buckled, it can move upwards during the impact, resulting in a strong impact on the abdomen, as in addition to the stopping force of the pregnant woman, the upward speed of the lap belt applies additional pressure on it. This pressure can result in a ruptured uterus or damage the formation of vital organs of the unborn baby. It has even been shown that some children have suffered irreparable damage due to the injuries caused by seatbelts while in their mother's womb.
Positioners are known that keep seatbelts in the correct position, but they only act on the lap belt, making it pass under the abdomen. This is the case of the positioners described in U.S. Pat. No. 6,935,700, U.S. Pat. No. 5,005,865, WO9008676 and EP1193143.
These positioners consist in a cushion placed on the seat of the vehicle in which the pregnant women is sitting that has an attachment element that passes between the thighs (in the case of U.S. Pat. No. 6,935,700, U.S. Pat. No. 5,005,865 and WO9008676) or two attachment elements on either side of the thighs (as described in patent EP1193143) that hold the lap belt, moving it towards the lower part of the abdomen.
Other positioners, such as that described in U.S. Pat. No. 7,270,347, simply comprise a strap joined to the seat at the headrest that runs down the back of the seat, passing over the seat base towards the front part of the seat, so that when the pregnant woman is sitting on it it passes between her thighs and holds down the lap belt.
A drawback of all the aforementioned devices is that they are joined to the vehicle seat, embracing the seat back or the headrest, so that they cannot be used correctly in all seats of the vehicle, such as in the rear seats. In addition, these devices only act on the lap belt and not on the shoulder strap, so that they do not prevent their incorrect positioning.
In addition, there are other positioners, such as that described in patent GB2423057, that act only on the shoulder strap and not on the lap belt. This devices consists in a harness that holds the pregnant woman by the torso, which is fastened to the shoulder strap at the rear, in the back, by a hook. With this system, the lap belt behaves exactly as if the device were not present, so that it does not keep it from riding over the pregnant woman's abdomen and in case of accident can potentially injure the unborn baby.
To solve the drawbacks of the state of the art, the present invention is proposed for a vehicle seatbelt positioner that acts on the shoulder strap and the lap belt, coupled to the user, easy to install and remove, which prevents an incorrect positioning of the seatbelt that could harm the user in case of accident.